Colour Vision: What Does It Mean and Why Does It Matter?

August 27, 2025

Colour vision is how your eyes tell the difference between colours. Most people can see colour normally, but about 1 in 12 men and 1 in 200 women are born with a colour vision deficiency, commonly known as colour blindness.


What Is Colour Blindness?

Colour blindness is usually inherited. It happens when the colour-sensing cells in your eyes (cones) don’t respond properly to red, green, or blue light.


The most common type is red-green deficiency, which makes it harder to tell those colours apart. Less common types affect blue-yellow vision, and a very rare form impacts all colours.


Signs of Colour Vision Deficiency

People with colour vision issues may:

- Struggle to tell red from green

- Have trouble reading colour-coded maps, charts or wiring diagrams

- Find colour-based tasks challenging at school

Does It Affect Daily Life?

Often, people adapt well and go about daily life without issue. But in some jobs, for example pilots, electricians and graphic designers, accurate colour vision is essential.


We provide colour vision assessments to meet licensing and occupational standards, including CASA aviation medicals.


Can Anything Help?

There’s no cure for colour blindness, but we offer iRo colour-enhancing lenses, which may improve contrast and colour separation for some patients.


More importantly, we help people understand their colour vision profile and provide tailored advice to make life easier at school, at work, or just day to day.


We’re Here to Help

At VISION Michael Hare Optometrists, we provide supportive, non-judgemental colour vision testing for children, adults, and those with job requirements. Whether you're exploring career options or just want clarity, we're here to help.

Related Articles:

→ CASA Eye Exam: What to Expect

→ Eye Health Assessment: What to Expect


References:

- Birch J. *Diagnosis of Defective Colour Vision*. Oxford University Press, 2001.

- Cole BL. The handicap of abnormal colour vision. *Clin Exp Optom*. 2004;87(4–5):258–275.

- Cumberland PM, Rahi JS. Prevalence of colour vision deficiency in boys and girls in primary schools: a study of 4,859 children. *Br J Ophthalmol*. 2016;100(1):123–127.

- International Civil Aviation Organization (ICAO). *Manual of Civil Aviation Medicine*, 3rd edition. ICAO; 2022.

Woman in dim light holds a phone, rubbing her tired eyes.

Blue Light and Digital Eye Strain; What You Really Need to Know

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You’ve probably heard that blue light from screens can damage your eyes, but is that actually true? Here’s what research shows: blue light from screens does not damage your eyes the way UV light does. However, spending hours on screens can still lead to digital eye strain, and evening screen time may interfere with your natural sleep-wake cycle.  Symptoms of Digital Eye Strain: - Tired, sore or gritty eyes - Blurred vision after screen time - Headaches or difficulty focusing - Dry eyes from reduced blinking - Trouble sleeping after late-night device use
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Blurry Vision: Sudden or Gradual?

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Blurry vision can happen all of a sudden or develop gradually over time. Understanding when it starts can help us figure out what’s going on. Sudden blurry vision may signal something more urgent, such as: Retinal detachment or tear Acute glaucoma attack Vascular events (like a blockage in eye blood vessels) Gradual blurry vision is often caused by: Refractive errors (myopia, hyperopia, astigmatism) Cataract development Dry eye disease Macular changes (like age-related macular degeneration)
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CASA Eye Exam: What to Expect

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If you’re applying for or renewing your aviation medical, you may need to complete a CASA eye exam with an optometrist. At VISION Michael Hare Optometrists, we regularly perform these assessments and know exactly what CASA requires. What is the CASA eye exam? This occupational assessment ensures your vision meets the safety standards for aviation. It covers a wide range of visual functions, not just how well you can read an eye chart.
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Cataracts: What are Cataracts? their causes and treatment

August 27, 2025
Noticing your vision getting cloudy or dimmer, especially when driving at night or dealing with glare? You might be developing cataracts, a condition where the eye’s natural lens becomes cloudy over time. Cataracts usually develop gradually as part of the ageing process. Other factors that can increase your risk include long-term UV exposure, smoking, diabetes, and certain medications. What Are the Symptoms? Cloudy, fuzzy, or film-like vision Increased sensitivity to bright light or glare Difficulty with night driving Colours looking faded or yellowed
Hands holding glasses in front of an eye chart, testing vision.

Comprehensive Eye Health Assessment: What We Check and Why

August 27, 2025
A routine eye test is about more than just reading letters on a chart. At VISION Michael Hare Optometrists , we offer comprehensive eye health assessments that check the full health of your eyes—inside and out. Many serious eye conditions can develop without symptoms. A proper exam lets us catch issues early, even before they affect your vision. What’s Included in a Comprehensive Eye Exam? External and internal slit lamp examination ; Checking the front and back of your eye Scans of the macula, optic nerve, and peripheral retina ; OCT when indicated and ultra-wide field retinal scans for thorough care Intraocular pressure testing ; Important for detecting glaucoma Visual field testing (automated perimetry, where indicated) Discussion of lifestyle, medications, and risk factors
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Contact Lenses: What Are My Options?

August 27, 2025
Contact lenses offer crisp vision and freedom from glasses—but with so many options available, how do you know what’s right for you? At VISION Michael Hare Optometrists, we help you navigate your choices to find lenses that suit your eyes, lifestyle, and vision needs. Soft Lenses Soft lenses are the most commonly prescribed and come in several options: Daily disposables: The most comfortable and hygienic option. Perfect for sensitive eyes, allergy sufferers, or anyone looking for low maintenance. Backed by research as the safest type of contact lens wear. Fortnightly/monthly lenses: More affordable for regular wearers but require more care. These lenses are safe and effective when used correctly but may carry slightly more risk of dryness or infection. Toric lenses: Designed to correct astigmatism. Multifocal lenses: Provide clear vision at all distances, ideal for those needing both near and distance focus.
Man having eye exam using a phoropter at an optometry clinic, being examined by a medical professional.

Diabetes and Your Eyes: Why Regular Checks Matter

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If you have diabetes, type 1 or type 2, it’s important to keep an eye on your eyes. High blood sugar can damage the delicate blood vessels at the back of the eye, leading to diabetic retinopathy, macular swelling, or even permanent vision loss. The tricky part? It often starts with no symptoms at all. Why Regular Diabetic Eye Checks Matter: Diabetic eye disease can be silent at first. Early detection gives the best chance to protect your vision. Medicare covers diabetic eye exams for eligible patients. We coordinate with your GP or specialist for complete care. Even if your blood sugars are well managed, regular eye exams are essential.
Woman putting eye drops in green eye. Close-up, indoor setting.

Dry Eye Treatment Options: What Works?

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Dry eye can be more than just annoying, it can make reading, working, or even enjoying the outdoors uncomfortable. At VISION Michael Hare Optometrists , we offer a full suite of treatment options tailored to your needs. What Causes Dry Eye? Dry eye occurs when your eyes don’t produce enough tears or when the tears evaporate too quickly. It can result from age, medications, hormonal changes, screen use, or certain health conditions.
Eye with subconjunctival hemorrhage, visible red blood pooling in the white of the eye.

Eye Injury: What to do

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Got something in your eye or suffered a bump to the face? Eye injuries can range from minor irritations to emergencies. Minor Injuries (like a small foreign object or minor scratch): Gently rinse your eye with clean water or saline. Avoid rubbing your eye as this can make things worse. If irritation persists, book an eye exam with VISION Michael Hare Optometrists.
Young boy wearing a phoropter at an eye exam, a doctor adjusting the lenses, smiling.

Eye Tests for Kids: What’s Involved and Why It Matters

August 27, 2025
Children rely on their vision to learn, play, and grow. But many vision problems go unnoticed, especially in younger kids who may not know how to describe what they’re seeing. That’s why regular eye tests are so important, even if everything seems fine. At VISION Michael Hare Optometrists , we make eye tests fun and age-appropriate. Our team is experienced with children of all ages, from toddlers to teens. Why Test Their Eyes? Vision develops rapidly in early childhood. Kids often don’t complain, they assume everyone sees the same way. Early detection helps prevent learning delays, behavioural concerns, and long-term vision problems. Even if your child sees well, an eye test helps us understand how hard their eyes are working to maintain that clarity.